Mother of pearl and silver: The Andalusian is one of the most finished of Whistler’s portraits of his sister-in-law, Ethel Birnie Philip. The title refers to Ethel’s silk evening dress; the transparent layered sleeves of the bolero jacket resembling traditional Andalusian costume. Ethel was particularly interested in clothes and, although not a wealthy woman, liked to dress as a member of high society in the latest Parisian fashions.